EENG 3910: Project V

1. EENG 3910: Project V Final Project: Audio Processor Beth Keswani Les Murphy Craig Robicheaux

2. Division Of Work • Beth Keswani • Create echo, multiple echo, and reverb • Help create Power Point • Help compile Final Project Report • Les Murphy • Create equalizers, pitch shifts • Provide material for Power Point • Help compile Final Project Report • Craig Robicheaux • Convert audio file to wav file • Create flanger, fade in, and fade out • Provide material for Final Project Report

3. Motivations • To create an audio processor, similar to an audio recording studio • To successfully create a Matlab project • To work together as a team

4. Objectives • To create an audio processor that can do several effects: • Echo • Multiple echo • Equalizer: • High band pass • Band pass • Low band pass • 3 types of Reverb • Pitch Shift • Low • High • Fade In • Fade Out • Flanger

5. Details • Each effect will include a definition, demonstration, and its corresponding code.

6. Echo • An echo is defined as a delayed reflection of sound. • We successfully heard an echo using our code.

7. Echo

8. Code

9. Multiple Echoes • Multiple echoes are several delayed reflections of sound. • Our code easily demonstrated this effect.

10. Multiple Echoes

11. Code

12. Equalizers • High band pass equalizers filter out low frequencies. • Low band pass equalizers filter out higher frequencies. • Band pass equalizers filter only frequencies within a selected range, and rejects frequencies outside the range. • We successfully created these three equalizers.

13. Code

14. Reverb • Reverb is several echoes that slowly decay as the sound is absorbed into the air and walls around it. • We were able to accomplish the code for our reverb.

15. Reverb

16. Code

17. Pitch Shifts • Pitch shift takes a frequency and raises or lowers it by a constant factor. • We were able to create two pitch shifts, one to raise and one to lower the frequencies of our audio files.

18. Code

19. Fade In • Fade in allows the music to begin softly and gradually get louder as the audio file plays. • Our code easily demonstrated this effect.

20. Code

21. Fade Out • Fade out allows the music to lower the volume in a constant change until it is silent at the end of the audio file. • We successfully created a fade out effect.

22. Code

23. Flanger • The purpose of a flanger is a time based audio effect that occurs when two identical signals are mixed together, but one signal is time delayed by a small and gradually changing amount, usually smaller than 20ms. • We successfully created a flanger effect.

24. Flanger

25. Code

26. Combined Code

27. Screen Shot

28. Conclusion • As a team, we successfully created an audio processor that could alter audio files with several effects. We used Matlab to create and implement our code. We use screen shots and code to exemplify our results.